This week is an exercise rather than a lesson. It takes about ten minutes and it is worth doing with a pen.
Two columns
Draw a line down a page. Left column: things I control. Right column: things I do not.
Now write down everything currently taking up room in your head about your sport. All of it. The ref. Your minutes. Whether the coach likes you. Your weak foot. The kid ahead of you on the depth chart. What your parents said in the car. The weather on Saturday.
Sort each one honestly.
What people get wrong
Two things, almost always.
Effort and attitude are never on the right. They feel like they depend on circumstances. They do not. They are the two things that stay yours on the worst day of the season.
Other people's opinions are never on the left. Not your coach's, not a scout's, not the group chat's. You can influence them with your behaviour, which lives on the left. You cannot control the conclusion, which lives on the right.
Most athletes have their columns backwards on exactly these two, and it costs them a lot of energy.
The point of the sort
Everything on the right still matters. You are not pretending it does not. You are deciding not to spend attention there during competition, because attention spent there produces nothing and there is a fixed amount of it.
Look at the left column. That is your job description. It is usually shorter than people expect and far more doable than the tangle it came out of.
This week's work
Do the two columns today. Keep the page.
Then, in your next game, every time you feel your attention drift to something in the right column — the ref, the score, who is watching — name one thing from the left column instead and do it.
Same trigger, better destination. That swap is the whole skill, and it gets faster with reps.
At the end of the week, look at the page again. Some things will have moved columns now that you have seen them written down.